FIG.1.

Induction of IFN-α/β in CEFs or GEFs infected with different influenza viruses. (A) CEFs or GEFs were infected with the tested influenza viruses, and the UV-treated supernatants were used to examine IFN-mediated inhibition of VSV-GFP replication in CEF and GEF cells, as described in Materials and Methods; the cells were visualized by fluorescence microscopy at 12 and 24 h p.i., respectively. (B) The supernatants of the VSV-GFP-infected cells were harvested at 12 and 24 h p.i. for determination of virus titers in CEFs. The short bars on the top indicate the standard deviation. (I) Supernatant harvested from influenza virus-infected CEFs; (II) supernatant harvested from influenza virus-infected GEFs. (C) RT-PCR analysis of IFN-α/β- and chicken β-actin-specific mRNAs in influenza virus-infected CEFs.